Assertion failure in Perl_pad_add_anon (pad.c:849)

[p5pRT]

Migrated from rt.perl.org#134009 (status was 'new')

Searchable as RT134009$

[p5pRT]

From @dur-randir

Created by @dur-randir

While fuzzing perl v5.29.9-63-g2496d8f3f7 built with afl and run
under libdislocator, I found the following program

eval q!s,,$0[sub{m[]]],;s,,$0[sub{m[]]],}}!

to cause an assertion failure

perl​: pad.c​:614​: Perl_pad_add_anon​: Assertion `!CvWEAKOUTSIDE((const
CV *)sv)' failed.

GDB stack trace is following

#0 __GI_raise (sig=sig@​entry=6) at ../sysdeps/unix/sysv/linux/raise.c​:50
#1 0x00007ffff7a22535 in __GI_abort () at abort.c​:79
#2 0x00007ffff7a2240f in __assert_fail_base (fmt=0x7ffff7b84ee0
"%s%s%s​:%u​: %s%sAssertion `%s' failed.\n%n",
  assertion=0x55555596175e "!CvWEAKOUTSIDE(func)",
file=0x5555559610e8 "pad.c", line=810, function=<optimized out>) at
assert.c​:92
#3 0x00007ffff7a300f2 in __GI___assert_fail (assertion=0x55555596175e
"!CvWEAKOUTSIDE(func)", file=0x5555559610e8 "pad.c", line=810,
  function=0x555555962480 <__PRETTY_FUNCTION__.18152>
"Perl_pad_add_anon") at assert.c​:101
#4 0x0000555555674ac4 in Perl_pad_add_anon (func=0x7ffff748b988,
optype=17) at pad.c​:810
#5 0x00005555555d165f in Perl_ck_anoncode (o=0x7ffff324dfd0) at op.c​:11104
#6 0x00005555555bad4b in Perl_newSVOP (type=17, flags=0,
sv=0x7ffff748b988) at op.c​:7363
#7 0x00005555555d10b5 in Perl_newANONATTRSUB (floor=177, proto=0x0,
attrs=0x0, block=0x7ffff4519dc8) at op.c​:10965
#8 0x000055555566f3c9 in Perl_yyparse (gramtype=258) at perly.y​:1072
#9 0x00005555558390a9 in S_doeval_compile (gimme=1 '\001',
outside=0x7ffff79fb9a0, seq=4294967265, hh=0x0) at pp_ctl.c​:3502
#10 0x0000555555840e44 in Perl_pp_entereval () at pp_ctl.c​:4478
#11 0x000055555570b895 in Perl_runops_debug () at dump.c​:2537
#12 0x00005555555ed560 in S_run_body (oldscope=1) at perl.c​:2716
#13 0x00005555555ecade in perl_run (my_perl=0x7ffff7dc9fff) at perl.c​:2639
#14 0x00005555555a114e in main (argc=4, argv=0x7fffffffe0b8,
env=0x7fffffffe0e0) at perlmain.c​:127

This is present from at least 5.8.8.

Perl Info

Flags:
    category=core
    severity=low

Site configuration information for perl 5.29.9:

Configured by dur-randir at Wed Feb 27 14:51:01 MSK 2019.

Summary of my perl5 (revision 5 version 29 subversion 9) configuration:
  Commit id: c1e47bad34ce1d9c84ed57c9b8978bcbd5a02e98
  Platform:
    osname=darwin
    osvers=13.4.0
    archname=darwin-thread-multi-2level
    uname='darwin isengard.local 13.4.0 darwin kernel version 13.4.0:
mon jan 11 18:17:34 pst 2016; root:xnu-2422.115.15~1release_x86_64
x86_64 '
    config_args='-de -Dusedevel -DDEBUGGING -Dusethreads'
    hint=recommended
    useposix=true
    d_sigaction=define
    useithreads=define
    usemultiplicity=define
    use64bitint=define
    use64bitall=define
    uselongdouble=undef
    usemymalloc=n
    default_inc_excludes_dot=define
    bincompat5005=undef
  Compiler:
    cc='cc'
    ccflags ='-fno-common -DPERL_DARWIN -mmacosx-version-min=10.9
-DDEBUGGING -fno-strict-aliasing -pipe -fstack-protector
-I/usr/local/include -DPERL_USE_SAFE_PUTENV'
    optimize='-O3 -g'
    cppflags='-fno-common -DPERL_DARWIN -mmacosx-version-min=10.9
-DDEBUGGING -fno-strict-aliasing -pipe -fstack-protector
-I/usr/local/include'
    ccversion=''
    gccversion='4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.56)'
    gccosandvers=''
    intsize=4
    longsize=8
    ptrsize=8
    doublesize=8
    byteorder=12345678
    doublekind=3
    d_longlong=define
    longlongsize=8
    d_longdbl=define
    longdblsize=16
    longdblkind=3
    ivtype='long'
    ivsize=8
    nvtype='double'
    nvsize=8
    Off_t='off_t'
    lseeksize=8
    alignbytes=8
    prototype=define
  Linker and Libraries:
    ld='cc'
    ldflags =' -mmacosx-version-min=10.9 -fstack-protector -L/usr/local/lib'
    libpth=/usr/local/lib
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../lib/clang/6.0/lib
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib
/usr/lib
    libs=-lpthread -lgdbm -ldbm -ldl -lm -lutil -lc
    perllibs=-lpthread -ldl -lm -lutil -lc
    libc=
    so=dylib
    useshrplib=false
    libperl=libperl.a
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_dlopen.xs
    dlext=bundle
    d_dlsymun=undef
    ccdlflags=' '
    cccdlflags=' '
    lddlflags=' -mmacosx-version-min=10.9 -bundle -undefined
dynamic_lookup -L/usr/local/lib -fstack-protector'



@INC for perl 5.29.9:
    lib
    /usr/local/lib/perl5/site_perl/5.29.9/darwin-thread-multi-2level
    /usr/local/lib/perl5/site_perl/5.29.9
    /usr/local/lib/perl5/5.29.9/darwin-thread-multi-2level
    /usr/local/lib/perl5/5.29.9


Environment for perl 5.29.9:
    DYLD_LIBRARY_PATH (unset)
    HOME=/Users/dur-randir
    LANG=en_US.UTF-8
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/Users/dur-randir/perlbrew/bin:/Users/dur-randir/perlbrew/perls/perl-5.22.1/bin:/usr/local/bin:/usr/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/texbin
    PERLBREW_HOME=/Users/dur-randir/.perlbrew
    PERLBREW_MANPATH=/Users/dur-randir/perlbrew/perls/perl-5.22.1/man
    PERLBREW_PATH=/Users/dur-randir/perlbrew/bin:/Users/dur-randir/perlbrew/perls/perl-5.22.1/bin
    PERLBREW_PERL=perl-5.22.1
    PERLBREW_ROOT=/Users/dur-randir/perlbrew
    PERLBREW_SHELLRC_VERSION=0.84
    PERLBREW_VERSION=0.84
    PERL_BADLANG (unset)
    SHELL=/usr/local/bin/zsh